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SOLVED read comments :: AttributeError: 'databaseWindow' object has no attribute 'menu' , in KivyMD

Im trying to add a MDDropDownMenu in my databaseWindow, but each time I try to access the menu, the app crashes with an error of "'databaseWindow' object has no attribute 'menu'". Im planning to use the dropdown menu as a list of options for the user to choose from so they can run a query. Im new to KivyMD and any assistance would be appreciated.
from kivymd.app import MDApp
from kivy.lang import Builder
from kivy.uix.widget import Widget
from kivy.uix.screenmanager import ScreenManager,Screen
from kivy.core.window import Window
from kivy.uix.label import Label
from kivy.uix.floatlayout import FloatLayout
from kivy.uix.popup import Popup
from kivymd.uix.datatables import MDDataTable
from kivy.metrics import dp
from kivy.uix.anchorlayout import AnchorLayout
from kivymd.uix.menu import MDDropdownMenu
from kivy.properties import ObjectProperty
import mysql.connector
class myLoginScreen(Screen):
def __init__(self, **kwargs):
super().__init__(**kwargs)
class databaseWindow(Screen):
def dbtable_menu(self):
layout = AnchorLayout()
menu_items = [
{
"text": f"Item {i}",
"right_text": f"R+{i}",
"right_icon": "apple-keyboard-command",
"left_icon": "git",
"viewclass": "Item",
"height": dp(54),
"on_release": lambda x=f"Item {i}": self.menu_callback(x),
} for i in range(5)
]
self.menu = MDDropdownMenu(
caller = self.manager.get_screen('database1').ids['button'],
items = menu_items,
width_mult=4,
)
self.add_widget(self.menu)
def menu_callback(self, text_item):
print(text_item)
self.manager.get_screen('database1').ids['button'].text = str(text_item)
class MainApp(MDApp):
def build(self):
self.screen = Builder.load_file('login3.kv')
sm = ScreenManager()
sm.add_widget(myLoginScreen(name='main'))
sm.add_widget(databaseWindow(name='database1'))
return sm
if __name__ == "__main__":
MainApp().run()
Here is the kivy file:
#:import Window kivy.core.window.Window
#:import utils kivy.utils
ScreenManager:
myLoginScreen:
databaseWindow:
<myLoginScreen>:
id:main
name:'main'
bg_color: (1,1,1,.3)
highlight_color1jbsidis: [0,0,0,0]
highlight_color2jbsidis: (0,0,0,.3)
canvas.before:
Color:
rgba: utils.get_color_from_hex('#0A609E')
Rectangle:
size: self.size
pos: self.pos
FloatLayout:
#Image:
# source: '/Users/logo.png'
# pos_hint: {'right':.99, 'top':.85}
# size_hint_y: None
# height: dp(40)
# size: self.size
# pos: self.pos
# allow_stretch: False
# keep_ratio: True
TextInput:
id: username
hint_text: "Username"
foreground_color: [1,1,1,1]
background_color: [0,0,0,0]
background_image: ""
background_normal: ""
background_active: ""
multiline: False
font_size: 40
size_hint: .7 ,.1 #.06
pos_hint: {'center_x':.5, 'center_y':.65} #'center_y':.8
canvas.before:
Color:
rgba: [1,1,1,.5]
RoundedRectangle:
size: self.size
pos: self.pos
radius: 10,
FloatLayout:
MDIconButton:
text: "[u]Reset password[/u]"
icon: 'account'
markup: True
color: Window.clearcolor
opposite_colors: True
pos_hint: {'center_x':.8, 'center_y':.65}
TextInput:
id: password
hint_text: "Password"
foreground_color: [1,1,1,1]
background_color: [0,0,0,0]
background_image: ""
background_normal: ""
background_active: ""
multiline: False
password: True
size_hint: .7 ,.1 #.06
font_size: 40
pos_hint: {'center_x':.5, 'center_y':.45}
canvas.before:
Color:
rgba: [1,1,1,.5]
RoundedRectangle:
size: self.size
pos: self.pos
radius: 10,
FloatLayout:
MDIconButton:
icon: 'lock-outline'
markup: True
color: Window.clearcolor
opposite_colors: True
pos_hint: {'center_x':.8, 'center_y':.45}
MDRaisedButton:
id: sign_button
text: "Sign In"
pos_hint: {"center_x": .5, "top": .3}
on_release:
app.root.current = "database1"
MDRaisedButton:
id: button
text: "Sign up"
size_hint: .2 ,.05
pos_hint: {"right": .85, "center_y": .1}
opacity: 1
disabled: False
bg_color: (0,0,0,1)
color: [0,0,0,1]
<databaseWindow>:
id: database1
name: 'database1'
canvas.before:
Color:
rgba: utils.get_color_from_hex('#0A609E')
Rectangle:
size: self.size
pos: self.pos
MDRaisedButton:
id: button
text: "PRESS ME"
pos_hint:{"center_x":.5, "center_y":0.5}
on_release: root.menu.open()
MDTopAppBar:
title: "Select ONLY 1 Row for Query"
pos_hint: {'top':1}
elevation: 5
MDBoxLayout:
orientation: 'vertical'
padding: 10
MDFloatingActionButton:
icon: 'logout-variant'
on_press:
app.root.current = 'main'
root.log_out()
# GUI for pop up window
<P>:
Label:
text : "Please enter valid information"
size_hint : 0.2, 0.1
pos_hint : {"x" : 0.3, "top" : 0.8}

Horizontally aligning buttons in kivy

This is how my program looks right now.
How can I position my button "Log in" to always be horizontally aligned with center? I've tried looking on Stack Overflow about similar stuff but nothing worked for me... If anyone can help me, I would be really thankful.
Here's my python code:
from kivy.lang import Builder
from kivy.uix.screenmanager import ScreenManager, Screen
from kivy.core.window import Window
from kivy.uix.gridlayout import GridLayout
import kivy.properties as kyprops
from kivy.uix.widget import Widget
from kivy.uix.image import Image
Builder.load_file("main.kv")
Window.clearcolor = (1,1,1,1)
# Declare both screens
class LoginScreen(Screen):
#txt_inpt = kyprops.ObjectProperty(None)
#def __init__(self):
pass
class InfoScreen(Screen):
pass
# Create the screen manager
sm = ScreenManager()
sm.add_widget(LoginScreen(name='Login'))
sm.add_widget(InfoScreen(name='Info'))
class TestApp(App):
def build(self):
return sm
if __name__ == '__main__':
TestApp().run()
Here is my .kv code:
#:import C kivy.utils.get_color_from_hex
<LoginScreen>:
RelativeLayout:
txt_inpt: txt_inpt
canvas:
Color:
rgba: C('#336699')
Line:
width: 2
rectangle: (0,self.height-50,self.width,0)
id: linija
Ellipse:
pos: self.width- 35, self.height-15
size: 7 , 7.0000000001
angle_start: 0
angle_end: 360
Ellipse:
pos: self.width- 35, self.height-27
size: 7 , 7.0000000001
angle_start: 0
angle_end: 360
Ellipse:
pos: self.width- 35, self.height-39
size: 7 , 7.0000000001
angle_start: 0
angle_end: 360
TextInput:
id: txt_inpt
password: True
multiline: False
hint_text: 'Username'
hint_text_color: C('#b3ccff')
size_hint_x: 0.9
size_hint_y: None
pos_hint: {"x":0.05, "top":0.8}
background_color: (1,1,1,0.2)
on_text_validate: root.manager.current = 'Info'
height: 30
pos: 300,60
TextInput:
id: txt_inpt
password: True
multiline: False
hint_text: 'Password'
hint_text_color: C('#b3ccff')
size_hint_x: 0.9
size_hint_y: None
pos_hint: {"x":0.05, "top":0.7}
background_color: (1,1,1,0.2)
on_text_validate: root.manager.current = 'Info'
height: 30
pos: 300,60
BoxLayout:
width: 1
pos: self.parent.pos # important!
orientation: 'vertical'
halign: 'center'
Button:
on_press: root.manager.current = 'Info'
background_color: C('#336699')
pos: self.pos
size: self.size
size: 80,30
size_hint: None, None
## NOTE: pos_hint: {"x":0.45, "top":0.6}
font_name: 'Droid.otf'
text: 'Log in'
<InfoScreen>:
BoxLayout:
Button:
text: 'My settings button'
Button:
text: 'Back to menu'
on_press: root.manager.current = 'Login'

Your line in kv:
pos: self.parent.pos # important!
is positioning the BoxLayout in the lower left corner of the RelativeLayout
You can center it by using pos_hint and minimum_width:
BoxLayout:
# width: 1
# pos: self.parent.pos # important!
pos_hint: {'center_x':0.5, 'y':0}
size_hint_x: None
width: self.minimum_width
orientation: 'vertical'

Why is Screens not loading in Kv Language?

I have an App with three toggle buttons in a fixed header that is an outside indented layout for screen manager. On initialisation, the Import screen must show i.e. self.ids.scrn_man.current = 'import_scn" and when a toggle button is pushed a next screen should show i.e. on_state: scrn_man.current = "settings_scrn".
But for some reason, only the header is showing and the screens do not want to transition. I don't get any errors.
I tried different layouts as my Apps main class inheritance including, FloatLayout, StackLayout and BoxLayout. I also made the header fixed with AnchorLayout and use a different layout as the inline layout for ScreenManager. If I remove the ScreenManager I see my widgets, but of course, I cannot transition. I did at first try using TabbedPanel to house my different widgets but I encountered a constant RefError: weak object reference if I added too many widgets (but that's not for now). So I re-designed with something I knew worked on a previous App albeit less complex.
Here is my faulty code:
from kivy.app import App
from kivy.uix.button import Button
from kivy.uix.stacklayout import StackLayout
from kivy.uix.togglebutton import ToggleButton
from kivy.lang import Builder
from kivy.uix.popup import Popup
from kivy.properties import StringProperty, ObjectProperty
Builder.load_string("""
<RoundedButton#Button>:
background_color: 0,0,0,0
canvas.before:
Color:
rgba: (.47,.47,.47,1) if self.state=='normal' else (1,.6,0,1)
RoundedRectangle:
pos: self.pos
size: self.size
radius: [8,]
<RoundedCancelButton#Button>:
background_color: 0,0,0,0
canvas.before:
Color:
rgba: (.47,.47,.47,1) if self.state=='normal' else (1,.2,.2,1)
RoundedRectangle:
pos: self.pos
size: self.size
radius: [8,]
<RoundedAcceptButton#Button>:
background_color: 0,0,0,0
canvas.before:
Color:
rgba: (.47,.47,.47,1) if self.state=='normal' else (.2,1,.6,1)
RoundedRectangle:
pos: self.pos
size: self.size
radius: [8,]
<TabbedContainer#ToggleButton>:
background_color: (1, .5, 0, 1)
background_normal: ''
size_hint_y: None
height: 50
size_hint_x: (1 / 3)
spacing: 30
<Tab>:
canvas.before:
Color:
rgba: (.89, .89, .89, 1)
Rectangle:
size: self.size
pos: self.pos
orientation: 'lr-tb'
BoxLayout:
orientation: 'horizontal'
size_hint_y: None
height: 30
canvas.before:
Color:
rgba: (1, .3, 0, 1)
Rectangle:
size: self.size
pos: self.pos
Label:
text: 'Test'
color: (1, 1, 1, 1)
size_hint_x: 1
StackLayout:
orientation: 'lr-tb'
Label:
text: ''
size_hint_x: 1
size_hint_y: None
height: 10
TabbedContainer:
id: import_tog
text: 'Import'
state: 'down'
group: 'admin_navs'
on_state: root.change_screen(self)
TabbedContainer:
id: calculate_tog
text: 'Calculate'
group: 'admin_navs'
on_state: root.change_screen(self)
TabbedContainer:
id: settings_tog
text: 'Settings'
group: 'admin_navs'
on_state: root.change_screen(self)
BoxLayout:
id: ui_content
padding: 10
ScreenManager: #Problem here I think
id: scrn_man
Screen:
id: import_scrn
name: 'import_scrn'
StackLayout:
orientation: 'lr-tb'
Label:
text: ''
size_hint_x: 1
Label:
text: ''
size_hint_x: 0.2
RoundedButton:
text: 'Choose File'
size_hint_x: 0.2
TextInput:
id: get_file
readonly: True
size_hint_x: 0.5
Label:
text: ''
size_hint_x: 0.1
Label:
text: ''
size_hint_x: 0.2
RoundedButton:
text: 'Import'
size_hint_x: 0.2
Label:
text: ''
size_hint_x: 0.6
StackLayout:
id: import_data_content
orientation: 'lr-tb'
size_hint_y: None
height: 90
Screen:
id: calculate_scrn
name: 'calculate_scrn'
Screen:
id: settings_scrn
name: 'settings_scrn'
StackLayout:
orientation: 'lr-tb'
size_hint_x: 0.5
Label:
text: ''
size_hint_x: 0.1
Button:
text: 'Add Employee'
size_hint_x: 0.2
Label:
text: ''
size_hint_x: 0.2
Button:
text: 'CSV'
size_hint_x: 0.2
Label:
text: ''
size_hint_x: 0.3
BoxLayout:
orientation: 'horizontal'
size_hint_x: 0.5
Label:
text: 'In Time'
size_hint_x: 0.7
TextInput:
size_hint_x: 0.3
Label:
text: 'Out Time'
size_hint_x: 0.7
TextInput:
size_hint_x: 0.3
""")
class TabbedContainer(ToggleButton):
pass
class FileChoosePopup(Popup):
load = ObjectProperty()
class RoundedButton(Button):
pass
class RoundedCancelButton(Button):
pass
class RoundedAcceptButton(Button):
pass
class Tab(StackLayout):
file_path = StringProperty("No file chosen")
the_popup = ObjectProperty(None)
def __init__(self, **kwargs):
super().__init__(**kwargs)
#load import window on initialisation
import_window = self.ids.import_scrn
self.ids.scrn_man.current = 'import_scrn'
def change_screen(self, instance):
if instance.text == 'Import':
self.ids.scrn_man.current = 'import_scrn'
elif instance.text == 'Calculate':
self.ids.scrn_man.current = 'calculate_scrn'
else:
self.ids.scrn_man.current = 'settings_scrn'
class TestApp(App):
def build(self):
return Tab()
if __name__ == '__main__':
TestApp().run()
I expect that the import screen must show on initialisation and screens transition on toggle button state: down. Can someone please give me some advice on how to make my App act as explained above?

Your screens are loading correctly according to your settings. You need to review your entire kv string looking at your size_hint settings. Check each item that contains children and make sure that the total of size_hint_x for its children is less than or equal to 1.0 and the same for size_hint_y.

Using jsonstore in Kivy

I created a GUI based off this question while trying to teach myself how to use jsonstore. I don't have the reputation points to add a comment so I'm asking my question here. I think I have the basic idea down but for some reason I can't save the data to a json file. I get the following error:
AttributeError: 'NoneType' object has no attribute 'text'
I've tried following the documentation but I can't see anywhere where it would explain what I'm doing wrong.
main.py
from kivy.storage.jsonstore import JsonStore
from kivy.app import App
from kivy.lang import Builder
from kivy.uix.screenmanager import Screen, ScreenManager
from kivy.core.window import Window
from kivy.uix.boxlayout import BoxLayout
from kivy.uix.widget import Widget
from kivy.properties import BooleanProperty, ListProperty, StringProperty, ObjectProperty
Window.clearcolor = (0.02745098, 0.074509804, 0.121568627, 1)
Window.size = (2000, 900)
class TitleScreen(Screen):
pass
class MainScreen(Screen):
pass
class CreateProfile(Screen):
First = ObjectProperty()
Middle = ObjectProperty()
Last = ObjectProperty()
def __init__(self, **kwargs):
super(CreateProfile, self).__init__(**kwargs)
self.store = JsonStore("bco.json")
self.load()
def save(self):
self.store.put('profile', first = self.label.text)
self.store.put('profile', middle = self.label.text)
self.store.put('profile', last = self.label.text)
def load(self):
try:
self.Last.text = self.store.get('profile')['score']
except KeyError:
pass
class CreatePacket(Screen):
pass
class ScreenManagement(ScreenManager):
pass
presentation = Builder.load_file("customwidget.kv")
class CustomWidgetApp(App):
def build(self):
return presentation
if __name__ == "__main__":
CustomWidgetApp().run()
customwidget.kv
#: import FadeTransition kivy.uix.screenmanager.FadeTransition
#: import hex kivy.utils.get_color_from_hex
#: import FocusBehaviors kivy.uix.behaviors.focus
ScreenManagement:
transition: FadeTransition()
TitleScreen:
MainScreen:
CreateProfile:
CreatePacket:
<MainLabel#Label>:
font_size:50
bold: True
size_hint_x: 1
size_hint_y: 1.85
color: 0.396078431, 0.803921569, 0.807843137, 1
font_name: '/home/jarren/PycharmProjects/BCO_Form_Filler/practice/pirulen rg.ttf'
<SubLabel#Label>:
font_size: 35
bold: True
halign: "center"
size_hint_x: 1
size_hint_y: 1.5
color: 0.396078431, 0.803921569, 0.807843137, 1
font_name: '/home/jarren/PycharmProjects/BCO_Form_Filler/practice/pirulen rg.ttf'
<OtherLabel#Label>:
font_size: 12
bold: True
color: 0.396078431, 0.803921569, 0.807843137, 1
font_name: '/home/jarren/PycharmProjects/BCO_Form_Filler/practice/pirulen rg.ttf'
text_size: self.size
<Button#Button>:
font_size: 20
bold: True
color: 0.396078431, 0.803921569, 0.807843137, 1
font_name: '/home/jarren/PycharmProjects/BCO_Form_Filler/practice/pirulen rg.ttf'
background_color: 0.02745098, 0.074509804, 0.121568627, .01
canvas.before:
Color:
rgba: 0.396078431, 0.803921569, 0.807843137, 1
Line:
width: 2
rectangle: self.x, self.y, self.width, self.height
on_press: self.background_color = (0.396078431, 0.803921569, 0.807843137, 1)
on_release: self.background_color = (0.02745098, 0.074509804, 0.121568627, .01)
# TODO: Create a focus behavior to "Tab" between widgets
<TextInput#TextInput>:
font_size: 12
color: 0.396078431, 0.803921569, 0.807843137, 1
font_name: '/home/jarren/PycharmProjects/BCO_Form_Filler/practice/pirulen rg.ttf'
padding_x: 10
padding_y: 10
focus_next: None
focus_previous: None
unfocus_on_touch: True
background_color: 0.02745098, 0.074509804, 0.121568627, .01
canvas.before:
Color:
rgba: 0.396078431, 0.803921569, 0.807843137, 1
Line:
width: 1
rectangle: self.x, self.y, self.width, self.height
<TitleScreen>:
id: "title"
FloatLayout:
MainLabel:
text: "Easy Button"
size_hint_x: 1
size_hint_y: 1.25
SubLabel:
text: 'Test'
size_hint_x: 1
size_hint_y: 1
Button:
text: "Click Here To Continue"
on_release: app.root.current = "main"
size_hint: (.75, .15)
pos_hint: {'x': .12, 'y': .2}
<MainScreen>:
name: "main"
MainLabel:
text: "Home Page"
BoxLayout:
Button:
on_release: app.root.current = "create_profile"
text: "Create Profile"
size_hint: (.5, .15)
Button:
on_release: app.root.current = "create_packet"
text: "Create Packet"
size_hint: (.5, .15)
<CreateProfile>:
name: "create_profile"
AnchorLayout:
anchor_x: 'center'
anchor_y: 'top'
MainLabel:
text: "Create Profile"
size_hint: (1, .15)
BoxLayout:
size_hint: (.95, .2)
pos_hint: {'x': 0, 'y': .85}
spacing: 10
padding: 10
halign: "left"
OtherLabel:
text: "First"
OtherLabel:
text: "Middle"
OtherLabel:
text: "Last"
BoxLayout:
size_hint: (.95, .07)
pos_hint: {'x': 0, 'y': .8}
spacing: 20
padding: 10
halign: "right"
text_size: self.size
TextInput:
id: 'First'
TextInput:
id: "Middle"
TextInput:
id: 'Last'
BoxLayout:
Button:
on_release: app.root.current = "main"
text: "back Home"
size_hint: (.5, .15)
Button:
on_release: root.save()
text: "Save Profile"
size_hint: (.5, .15)
<CreatePacket>:
name: "create_packet"
MainLabel:
text: "Select Packet"
FloatLayout:
Button:
on_release: app.root.current = "main"
text: "back Home"
size_hint: (1, .15)

Your code has several problems but the main one is that you do not understand how to expose any .kv widget to .py, one of the simplest ways is to use an ObjectProperty as you try to do but that property is not linked to the widget, I prefer to do the creation in the .kv for its simplicity.
On the other hand I recommend you avoid the abuse of try-except since it hides errors, the best thing is to verify.
Another error is that you are overwriting the value of profile in the .json, the idea is to save everything in one.
Considering the above, the solution is:
*.py
from kivy.app import App
from kivy.storage.jsonstore import JsonStore
from kivy.lang import Builder
from kivy.uix.screenmanager import Screen, ScreenManager
from kivy.core.window import Window
from kivy.clock import Clock
Window.clearcolor = (0.02745098, 0.074509804, 0.121568627, 1)
Window.size = (2000, 900)
class TitleScreen(Screen):
pass
class MainScreen(Screen):
pass
class CreateProfile(Screen):
def __init__(self, **kwargs):
super(CreateProfile, self).__init__(**kwargs)
self.store = JsonStore("bco.json")
Clock.schedule_once(lambda *args: self.load())
def save(self):
self.store.put('profile',
first = self.first.text,
middle = self.middle.text,
last = self.last.text)
def load(self):
if self.store.exists('profile'):
profile = self.store.get('profile')
v = [("first", self.first), ("middle", self.middle), ("last", self.last)]
for key, ti in v:
val = profile.get(key)
if val:
ti.text = val
class CreatePacket(Screen):
pass
class ScreenManagement(ScreenManager):
pass
presentation = Builder.load_file("customwidget.kv")
class CustomWidgetApp(App):
def build(self):
return presentation
if __name__ == "__main__":
CustomWidgetApp().run()
*.kv
#: import FadeTransition kivy.uix.screenmanager.FadeTransition
#: import hex kivy.utils.get_color_from_hex
#: import FocusBehaviors kivy.uix.behaviors.focus
ScreenManagement:
transition: FadeTransition()
TitleScreen:
MainScreen:
CreateProfile:
CreatePacket:
<MainLabel#Label>:
font_size:50
bold: True
size_hint_x: 1
size_hint_y: 1.85
color: 0.396078431, 0.803921569, 0.807843137, 1
font_name: '/home/jarren/PycharmProjects/BCO_Form_Filler/practice/pirulen rg.ttf'
<SubLabel#Label>:
font_size: 35
bold: True
halign: "center"
size_hint_x: 1
size_hint_y: 1.5
color: 0.396078431, 0.803921569, 0.807843137, 1
font_name: '/home/jarren/PycharmProjects/BCO_Form_Filler/practice/pirulen rg.ttf'
<OtherLabel#Label>:
font_size: 12
bold: True
color: 0.396078431, 0.803921569, 0.807843137, 1
font_name: '/home/jarren/PycharmProjects/BCO_Form_Filler/practice/pirulen rg.ttf'
text_size: self.size
<Button#Button>:
font_size: 20
bold: True
color: 0.396078431, 0.803921569, 0.807843137, 1
font_name: '/home/jarren/PycharmProjects/BCO_Form_Filler/practice/pirulen rg.ttf'
background_color: 0.02745098, 0.074509804, 0.121568627, .01
canvas.before:
Color:
rgba: 0.396078431, 0.803921569, 0.807843137, 1
Line:
width: 2
rectangle: self.x, self.y, self.width, self.height
on_press: self.background_color = (0.396078431, 0.803921569, 0.807843137, 1)
on_release: self.background_color = (0.02745098, 0.074509804, 0.121568627, .01)
# TODO: Create a focus behavior to "Tab" between widgets
<TextInput#TextInput>:
font_size: 12
color: 0.396078431, 0.803921569, 0.807843137, 1
font_name: '/home/jarren/PycharmProjects/BCO_Form_Filler/practice/pirulen rg.ttf'
padding_x: 10
padding_y: 10
focus_next: None
focus_previous: None
unfocus_on_touch: True
background_color: 0.02745098, 0.074509804, 0.121568627, .01
canvas.before:
Color:
rgba: 0.396078431, 0.803921569, 0.807843137, 1
Line:
width: 1
rectangle: self.x, self.y, self.width, self.height
<TitleScreen>:
id: "title"
FloatLayout:
MainLabel:
text: "Easy Button"
size_hint_x: 1
size_hint_y: 1.25
SubLabel:
text: 'Test'
size_hint_x: 1
size_hint_y: 1
Button:
text: "Click Here To Continue"
on_release: app.root.current = "main"
size_hint: (.75, .15)
pos_hint: {'x': .12, 'y': .2}
<MainScreen>:
name: "main"
MainLabel:
text: "Home Page"
BoxLayout:
Button:
on_release: app.root.current = "create_profile"
text: "Create Profile"
size_hint: (.5, .15)
Button:
on_release: app.root.current = "create_packet"
text: "Create Packet"
size_hint: (.5, .15)
<CreateProfile>:
name: "create_profile"
first: first
middle: middle
last: last
AnchorLayout:
anchor_x: 'center'
anchor_y: 'top'
MainLabel:
text: "Create Profile"
size_hint: (1, .15)
BoxLayout:
size_hint: (.95, .2)
pos_hint: {'x': 0, 'y': .85}
spacing: 10
padding: 10
halign: "left"
OtherLabel:
text: "First"
OtherLabel:
text: "Middle"
OtherLabel:
text: "Last"
BoxLayout:
size_hint: (.95, .07)
pos_hint: {'x': 0, 'y': .8}
spacing: 20
padding: 10
halign: "right"
text_size: self.size
TextInput:
id: first
TextInput:
id: middle
TextInput:
id: last
BoxLayout:
Button:
on_release: app.root.current = "main"
text: "back Home"
size_hint: (.5, .15)
Button:
on_release: root.save()
text: "Save Profile"
size_hint: (.5, .15)
<CreatePacket>:
name: "create_packet"
MainLabel:
text: "Select Packet"
FloatLayout:
Button:
on_release: app.root.current = "main"
text: "back Home"
size_hint: (1, .15)

I found a work around that still allows me to append information into a JSON by using TinyDB. Here is the updated code:
from kivy.app import App
from kivy.storage.jsonstore import JsonStore
from kivy.lang import Builder
from kivy.uix.screenmanager import Screen, ScreenManager
from kivy.core.window import Window
from tinydb import TinyDB, Query
from kivy.uix.listview import ListItemButton
Window.clearcolor = (0.02745098, 0.074509804, 0.121568627, 1)
Window.size = (2000, 900)
db = TinyDB('bcodb.json')
class ProfileListButton(ListItemButton):
pass
class TitleScreen(Screen):
pass
class MainScreen(Screen):
pass
class CreateProfile(Screen):
def __init__(self, **kwargs):
super(CreateProfile, self).__init__(**kwargs)
self.store = JsonStore("bcodb.json")
def save(self):
db.insert({'first': self.first.text, 'middle': self.middle.text, 'last': self.last.text})
def update(self):
db.update({'first': self.first.text, 'middle': self.middle.text, 'last': self.last.text})
class CreatePacket(Screen):
pass
class ScreenManagement(ScreenManager):
pass
presentation = Builder.load_file("customwidget2.kv")
class CustomWidgetApp(App):
def build(self):
return presentation
if __name__ == "__main__":
CustomWidgetApp().run()
It's pretty easy to figure out with a simple database-like program I'm trying to develop. The .kv file is the same.

How to change text of a label in the kivy language with python

I was wondering how I could change the text of a label made inside the Kivy language using Python.
Like how would I have user input from python be made as the text of a label in kivy.
(By the way I have the formatting correct in the actual program but I screwed up pasting it to stackoverflow)
Say if I wanted to make the text of the label in from the code be a random number generated in python how would I go about doing that?
from kivy.app import App
from kivy.lang import Builder
from kivy.uix.screenmanager import ScreenManager, Screen
from kivy.graphics import Color, Rectangle
from kivy.properties import ObjectProperty
# Create both screens. Please note the root.manager.current: this is how
# you can control the ScreenManager from kv. Each screen has by default a
# property manager that gives you the instance of the ScreenManager used.
Builder.load_string("""
<ButImage#ButtonBehavior+AsyncImage>
<TutImage#ButtonBehavior+AsyncImage>
<MenuScreen>:
GridLayout:
cols: 4
row_force_default: True
col_default_width: 175
row_default_height: 150
padding: 15
spacing: 15
canvas.before:
BorderImage:
# BorderImage behaves like the CSS BorderImage
border: 10, 10, 10, 10
source: '/Users/clayhigh/Desktop/kivy/aot.png'
pos: self.pos
size: self.size
Button:
text: 'Goto settings'
background_color: 1,0,0,0.5
on_press: root.manager.current = 'settings'
ButImage:
on_press: root.manager.current = 'UBW'
id: but
size_hint: .5, .5
opacity: 1 if self.state == 'normal' else .5
allow_stretch: True
keep_ratio: False
source: 'http://s3.amazonaws.com/rapgenius/1361742626_beautiful-ocean-beautiful-pictures-27115524-1440-900.jpg'
Label:
center: but.center
text: "UBW"
color: 0.78,0.145,0.016,2
ButImage:
id: lh
size_hint: .5, .5
opacity: 1 if self.state == 'normal' else .5
allow_stretch: True
keep_ratio: False
source: 'http://s3.amazonaws.com/rapgenius/1361742626_beautiful-ocean-beautiful-pictures-27115524-1440-900.jpg'
Label:
center: lh.center
text: "LH 2"
color: 0,0,0,1
ButImage:
id: ttl
size_hint: .5, .5
opacity: 1 if self.state == 'normal' else .5
allow_stretch: True
keep_ratio: False
source: 'http://s3.amazonaws.com/rapgenius/1361742626_beautiful-ocean-beautiful-pictures-27115524-1440-900.jpg'
Label:
center: ttl.center
text: "TwTl"
color: 0,0,0,1
ButImage:
id: gris
size_hint: .5, .5
opacity: 1 if self.state == 'normal' else .5
allow_stretch: True
keep_ratio: False
source: 'http://s3.amazonaws.com/rapgenius/1361742626_beautiful-ocean-beautiful-pictures-27115524-1440-900.jpg'
Label:
center: gris.center
text: "Gris"
color: 0,0,0,1
ButImage:
id: shig
size_hint: .5, .5
opacity: 1 if self.state == 'normal' else .5
allow_stretch: True
keep_ratio: False
source: 'http://s3.amazonaws.com/rapgenius/1361742626_beautiful-ocean-beautiful-pictures-27115524-1440-900.jpg'
Label:
center: shig.center
text: "Shig"
color: 0,0,0,1
Button:
text: 'Test3'
background_color: 1,0,0,0.5
Button:
text: 'Test4'
background_color: 1,0,0,0.5
Button:
text: 'Quit'
background_color: 1,0,0,0.5
on_press: App.on_stop
<SettingsScreen>:
GridLayout:
row_force_default: True
row_default_height: 100
cols: 2
canvas.before:
BorderImage:
# BorderImage behaves like the CSS BorderImage
border: 10, 10, 10, 10
source: '/Users/clayhigh/Desktop/kivy/ato.jpeg'
pos: self.pos
size: self.size
Button:
text: 'Button'
color: 0,0,.5
background_color: 1,0,0,1
Button:
text: 'Back to menu'
background_color: 1,0,0,1
on_press: root.manager.current = 'menu'
<UBW>:
GridLayout:
row_force_default: True
row_default_height: 100
cols: 2
canvas.before:
Color:
rgb: .5, .5, .5
Rectangle:
pos: self.pos
size: self.size
Color:
rgb: 1, 1, 1
BorderImage:
# BorderImage behaves like the CSS BorderImage
border: 10, 10, 10, 10
source: '/Users/clayhigh/Desktop/kivy/fsn.jpg'
pos: self.pos
size: self.size
Button:
text: 'Back to menu'
color: 0,0,.5
on_press: root.manager.current = 'menu'
background_color: 1,0,0,1
Label:
id: AName
text: "F S/N: UBW"
font_size: '24sp'
""")
# Declare both screens
class MenuScreen(Screen):
pass
class SettingsScreen(Screen):
pass
class UBW(Screen):
pass
# Create the screen manager
sm = ScreenManager()
sm.add_widget(MenuScreen(name='menu'))
sm.add_widget(SettingsScreen(name='settings'))
sm.add_widget(UBW(name='UBW'))
class TestApp(App):
def build(self):
return sm
if __name__ == '__main__':
TestApp().run()

Text of a label can be a kivy property, which can be later changed and since it is a kivy property it will automatically updated everywhere. Here is an example of your .py
from kivy.app import App
from kivy.uix.widget import Widget
from kivy.properties import StringProperty
import random
class YourWidget(Widget):
random_number = StringProperty()
def __init__(self, **kwargs):
super(YourWidget, self).__init__(**kwargs)
self.random_number = str(random.randint(1, 100))
def change_text(self):
self.random_number = str(random.randint(1, 100))
class YourApp(App):
def build(self):
return YourWidget()
if __name__ == '__main__':
YourApp().run()
and your .kv
<YourWidget>:
BoxLayout:
size: root.size
Button:
id: button1
text: "Change text"
on_release: root.change_text()
Label:
id: label1
text: root.random_number
When you click the button, it will call change_text() function, which will randomly change the text of the label to random integer between 1 and 100.